Separation of olive oil from olives
Olives are found in the biosphere (the crust). Olives have properties which are used to separate the mixture and improve the final product. Olive oil is less dense than water and can be separated by centrifugation. Olive oil cannot be dissolved in water, which makes it easier to separate. The seeds are very large and easily removed by a mashing method.
There are three stages to the separation, crushing, beating and centrifuging. Centrifuging is the first stage when the olive is crushed in a metal hammer mill to produce a paste. Beating is the next stage where water is added to the paste and beaten to remove more oil. Salt is sometimes added to help with the breakdown of the cells and release of oil. Centrifuging is the last stage; the mixture is placed in a centrifuge and spun at high speed. The light oil forms the upper layer and water and heavier fruit fragments forms the bottom layers. The upper oil layer continuously overflows a barrier and collected through a separate portal. Water is removed by rotating internal scrolls through a separate exit. The pulp is discharged using rotating internal scrolls.
There are no waste management issues that could affect the environment or society in this process. The products of separation are the olive oil, seeds and pulp waste. The olive oil is an important natural product that we use for cooking and the dried pulp waste is used in some fuels, mulch, fertilisers and animal feed. The majority of seeds are discarded but some are collected to be planted and grow new olive trees.